Endangered Species
What is an Endangered Species?
• An endangered species is a population of organisms
which is at risk of becoming extinct because it is
either few in numbers, threatened by changing
environmental or predation parameters,
deforestation, or lack of food or water.
• International and national agencies work to maintain
lists of endangered species, to protect and preserve
natural habitats, and to promote programs for
recovery and reestablishment of these species
What is an Extinct Species?
• Extinction is the disappearance of an entire species
• If a species does not have the genetic traits to survive in its
environment, then the species will eventually become extinct forever
• Some examples of extinct animals are:
Galapagos Tortoise
Bali Tiger
Dinosaurs
Thylacine
Steller’s Sea Cow
Quagga
Laughing Owl
Dodo Bird
Northern Hairy-nosed
Wombat
African Elephant
Endangered Species
Giant Armadillo
Black Rhinoceros
Chinese
Paddlefish
Snow Leopard
Wild Bactrian Camel
All of these species, along with hundreds of others are currently endangered
Cochabamba Mountain Finch
Right Whale
Red Wolf
Golden Lion Tamarin
Asiatic Cheetah
Hawaiian Crow
Short Tailed Chinchilla
Causes of Endangerment
• There are many different reasons that a species may
become endangered or extinct. Some of them that we will
explore today are:
 Rarity
 Inbreeding
 Hybridization
 Gradual loss of habitat
 Long-term environmental trends
 Catastrophe
 Extinction or reduction of mutualistic population
 Competition
 Predators
 Disease
 Hunting and collecting
Causes of Endangerment
• Rarity- when there are very few animals of a species left there are
less available mates
– Animals can be rare if they have very specific food or nesting
requirements, are sensitive to change, compete with other
species, migrate, or interfere with human activities in some way.
(Galapagos tortoise became rare because of their lack of ability
to compete with other species)
• Inbreeding- when animals mate too much within their own group
the offspring become less able to survive and adapt in a healthy way
– Below is a picture of an inbred white tiger with visible birth defects due
to inbreeding.
Causes of Endangerment
• Hybridization- When two animals from different
sub-species mate, they might pass on genes
that are less healthy (Quagga-half horse half
zebra which is now extinct)
• Gradual loss of habitat- When an animal's
habitat is slowly destroyed and they have
nowhere to live. (Bali Tiger, also now extinct)
Causes of Endangerment
• Long-term environmental trends- Scientists
think that dinosaurs became extinct because of
a slow cooling of the earth
• Catastrophe- Volcanic eruption, dramatic
change in climate, tsunami, etc.
Causes of Endangerment
• Extinction or reduction of mutualistic population- If
two species are dependent on each other, then the
endangering of one also endangers the other
– the Ocellaris clownfish that dwell among the tentacles of Ritteri sea
anemones would become endangered if the anemones were to become
endangered
• Competition- When a new species is introduced to a
habitat, then the stronger of the two species will be more
likely to survive.
– A Japanese vine introduced in a Georgia forest competes with the other
plants for light…and clearly wins.
Causes of Endangerment
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Predators- When the population of a species of predator in a habitat
suddenly increases, the population of their prey decreases
– The wolves in Yellow Stone National Park prevent herbivores from overgrazing the area by preying on them, thus increasing their risk of
endangerment
Disease- If a particular sickness spreads quickly throughout a particular
species, then many may die before they can reproduce
– The Tasmanian Devil Tumor Disease has made the species become
endangered
Hunting and collecting- Hunters have been largely responsible for the
endangerment of many animal species.
– Elephant poachers have been the cause of many endangered and
extinct species of elephants. Elephants have long been hunted and
killed for their valuable ivory tusks
Why Save Endangered Species?
“Plants and animals hold medicinal,
agricultural, ecological, commercial and
aesthetic/recreational value. Endangered
species must be protected and saved so that
future generations can experience their
presence and value.”
Medicinal
• About 40% of all prescriptions written today are
composed from the natural compounds of
different species
• The Pacific Yew 
is a tree that used to
be considered a “trash tree.”
It was discovered to be a
promising treatment for
some cancers.
Agricultural
• Scientists estimate there
are about 80,000 edible
plants in the world
• Only 20 species of these
plants (wheat, corn, etc)
provide most of the world’s
food.
• Animals, too, are part of
the agriculture. For
example, having birds eat
certain insects so that they
do not devour all of the
farmer’s crops
Ecological
• Plant and animal systems are the foundation of
healthy ecosystems. When a species becomes
endangered it is an indicator that the health of
these vital ecosystems is beginning to unravel.
• The US Fish and Wildlife Service estimates that
losing one plant species can trigger the loss of up
to 30 other insect, plant, and higher animal
species
• Pollution off the coast of Florida is killing the coral
reefs along the Florida Keys, which serve as a
habitat for hundreds of fish. Commercial fish
species have begun to decline causing a threat
to the tourism industry which depends on the
quality of the environment
Commercial
• Various wild species are
commercially raised, directly
contributing to local and regional
economies.
• For example, commercial salmon
fishing in the Pacific Northwest
provides 60,000 jobs and $1 billion
dollars a year in income. This
industry is in trouble as salmon
decline due to habitat degradation
from dams, clear cutting, and
overgrazing.
Recreational
• Plant and animal species and their
ecosystems form the basis of
America’s multi billion dollar job
intensive tourism industry. They
also supply recreation, spiritual,
and quality of life values as well.
• Each year over 100 million people
in the US participate in wildlife
related recreation including
observing, feeding and
photographing wildlife.
Laws That Protect Endangered Species
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Bald and Golden Eagle Protection Act
– Makes it illegal to import, export, or take bald or golden eagles to sell, purchase, or
barter their parts, or products made from them including their nests or eggs.
Marine Mammal Protection Act
– This Act establishes a moratorium on the taking and importation of marine mammals,
including parts and products, and defines Federal responsibility for conservation of
marine mammals, with management authority vested in the Department of the Interior
for the sea otter, walrus, polar bear, dugong, and manatee
Endangered Species Act
– This Act prohibits the importation, exportation, taking, and commercialization in
interstate or foreign commerce of fish and wildlife, and plants that are listed as
threatened or endangered species. The Act also implements the provision of the
Convention on the International Trade in Endangered Species of Wild Fauna and Flora.
Antarctic Conservation Act (16 U.S.C. 2401).
– The purpose of the Act is to provide for the conservation and protection of the fauna
and flora of Antarctica and of the ecosystem upon which such fauna and flora depend.
The primary prohibitions of the Act make it unlawful for any United States citizen to
take any native bird or mammal in Antarctica or to collect any native plant from any
specially protected area within Antarctica. In addition, the Act makes it unlawful for any
United States citizen or any foreign person in the United States to possess, sell, offer for
sale, deliver, receive, carry, transport, import, export, or attempt to import or export
from the United States any native mammal or bird taken in Antarctica or any plant
collected in any specially protected area.
THERE ARE MANY OTHER LAWS SET IN PLACE TO PRESERVE AND PROTECT ENDANGERED SPECIES